In the present study,gel formulations of organogels,hydrogels,and oleo-hydrogel(bigels)were evaluated as transdermal drug delivery systems for diltiazem HCL(DH).Organogels were prepared using soya-bean oil(SO)as a sol...In the present study,gel formulations of organogels,hydrogels,and oleo-hydrogel(bigels)were evaluated as transdermal drug delivery systems for diltiazem HCL(DH).Organogels were prepared using soya-bean oil(SO)as a solvent and span 60(Sp 60),cetyl alcohol(CA)or lecithinpluronic(PLO)as organogelators without and with different surfactants(2%w/w)namely span 80(Sp80),tween 20(T20)and tween 80(T80).On the other hand,hydrogels were formulated using Hydroxypropyl-methylcellulose(HPMC)polymer and bigels were prepared by mixing organogels with HPMC hydrogels.The prepared gels were analyzed microscopically,thermally by DTA and for pH,and viscosity.The effect of gelator used,surfactant types and pH of the sink on DH release from cellophane membrane was investigated.In addition,the DH permeability across the rabbit skin was evaluated.Finally,the in vivo performance of various gel formulationswas assessed based on the hypotensive effects of the drug using hypertensive albino male rat models.The microscopical analysis indicated that the solid fibers formed by gelator particles form the backbone of the organogels while bigels appeared as emulsion like.The addition of surfactants showed an increase in organogel viscosity.The thermal analysis of organogels indicated that the drug present in amorphous not in crystalline form.The release studies indicated that DH release from organogels,hydrogels and bigels could be controlled.The included surfactants decreased the DH release and permeation from organogels compared to those without surfactants using either Sp60 or CA.HPMC hydrogel and Bigels showed higher DH release and permeation rates when compared to organogels.The percent DH released in different pH values was in the following descending order:pH5.5>pH1.2>pH6.8>pH7.4.The in vivo antihypertensive activity of DH using different transdermal gels is arranged as following:hydrogels>PLO organogel>bigel>Sp 60 organogel.展开更多
Owing to their inherent semi-solid property and lubricant ability,organogels manifest various unique characteristics and serve as promising candidates for antifouling.However,the poor mechanical properties of organoge...Owing to their inherent semi-solid property and lubricant ability,organogels manifest various unique characteristics and serve as promising candidates for antifouling.However,the poor mechanical properties of organogels often limit their practical applications.Herein,we report a simple and effective method to prepare organogels with reinforced mechanical performance and surface lubricant ability with the synergistic roles played by oleophobic and oleophilic chains.The rigid oleophobic chains have a poor affinity to lubricating solvent,which gives rise to high oleophobic interactions between polymer networks;the soft oleophilic chains possess a high affinity to the low surface energy solvent,which lead to high solvent content to maintain the satisfactory lubricant capacity.The organogel of oleophobic methyl methacrylate(MMA)and oleophilic lauryl methacrylate(LMA)is chosen as a representative example to illustrate this concept.With the optimal composition,the as-prepared organogels offer satisfactory tensile fracture stress,fracture strain,Young’s modulus,toughness,and tearing fracture energy of 480 k Pa,550%,202 k Pa,1.14 MJ m,and 5.14 k J m,respectively,which are far beyond the classical PLMA organogels.Furthermore,the biofouling resistance tests demonstrate 4 to 9-fold reduction of protein and bacteria adhesion on the reinforced organogels surface in comparison to the glass substrate and solvent-free dry organogels.This simple and effective approach to toughen organogels,we hope,can be applied in various fields with different practical functional requirements in the future.展开更多
Fluorescent supramolecular nucleoside-based organogels or hydrogels have attracted increasing attention owing to their tunable stability,drug delivery,tissue engineering,and inherent biocompatibility for applications ...Fluorescent supramolecular nucleoside-based organogels or hydrogels have attracted increasing attention owing to their tunable stability,drug delivery,tissue engineering,and inherent biocompatibility for applications in designing sensors.As the temperature of a constant TPE-Octa-dU gelato r at MGC as low as 0.2 wt%was increased with gel to sol transition,a progressive decrease in the fluorescence intensity was observed.~1 H NMR study in ethanol-d_(6)/H_(2)O revealed the existence of intermolecular hydrogen-bond interaction between uridine nucleobase and triazole moieties.Based on these experiments,thus organogels induced by hydrogen bonding can promote an aggregation-induced emission(AIE)of TPE moiety.Thermoreversible gelation properties have been investigated systematically,including AIE-shapemorphing architecture owing to their unique solid-liquid interface and easy processability.At the same line,the related TPE-EdU derivative which was synthesized from 5-ethynyl-2'-deoxyuridine does not delive r organogels or hydrogels,a nd under similar circumstances TPE moiety of TPE-EdU does not efficiently exhibit AIE phenomenon either.展开更多
Supramolecular organogels were highly promising matrices for triplet-triplet annihilation-based upconversion(TTA-UC),but the dispersion and diffusion of the UC components were greatly relied on the microscopically int...Supramolecular organogels were highly promising matrices for triplet-triplet annihilation-based upconversion(TTA-UC),but the dispersion and diffusion of the UC components were greatly relied on the microscopically interconnected solution phase in gels.Herein,12-hydroxystearic acid(CA)and its derivatives with different alkyl chain(CA3,CA4,CA6 and CA8)were synthesized as low-molecular-weight gelators(LMMGs),and D-1 with CA attached on DPA unit was synthesized as annihilator.It was found that by co-assembling D-1 with the LMMGs,the DPA units were uniformly dispersed in the gel network regardless of whether there was a solvent or not.By chemically tuning LMMGs to optimize the morphologies of organogels,the DPA units were orderly arranged in the gel network,and showing efficient UC emission in CA,CA3,and CA8 which showed more regular morphologies.UC quantum yield of up to 13.4%(out of 50%maximum)was achieved in CA3 organogel.Moreover,when all solvents were removed from the organogels,D-1 also showed significant UC emissions,which was more than 6-fold higher than that of DPA,indicating that co-assembling the annihilator with the matrix to achieve an order arrangement presented an efficient strategy towards efficient TTA-UC in solid state.展开更多
Wearable sensors integrated with deep learning techniques have the potential to revolutionize seamless human-machine interfaces for real-time health monitoring,clinical diagnosis,and robotic applications.Nevertheless,...Wearable sensors integrated with deep learning techniques have the potential to revolutionize seamless human-machine interfaces for real-time health monitoring,clinical diagnosis,and robotic applications.Nevertheless,it remains a critical challenge to simultaneously achieve desirable mechanical and electrical performance along with biocompatibility,adhesion,self-healing,and environmental robustness with excellent sensing metrics.Herein,we report a multifunctional,anti-freezing,selfadhesive,and self-healable organogel pressure sensor composed of cobalt nanoparticle encapsulated nitrogen-doped carbon nanotubes(CoN CNT)embedded in a polyvinyl alcohol-gelatin(PVA/GLE)matrix.Fabricated using a binary solvent system of water and ethylene glycol(EG),the CoN CNT/PVA/GLE organogel exhibits excellent flexibility,biocompatibility,and temperature tolerance with remarkable environmental stability.Electrochemical impedance spectroscopy confirms near-stable performance across a broad humidity range(40%-95%RH).Freeze-tolerant conductivity under sub-zero conditions(-20℃)is attributed to the synergistic role of CoN CNT and EG,preserving mobility and network integrity.The Co N CNT/PVA/GLE organogel sensor exhibits high sensitivity of 5.75 k Pa^(-1)in the detection range from 0 to 20 k Pa,ideal for subtle biomechanical motion detection.A smart human-machine interface for English letter recognition using deep learning achieved 98%accuracy.The organogel sensor utility was extended to detect human gestures like finger bending,wrist motion,and throat vibration during speech.展开更多
Low-molecular-weight organogels(LMOG) have been attracting a surge interest in fabricating soft materials.Although the finding of the gelator molecules has been developed from serendipity to objective design,the achie...Low-molecular-weight organogels(LMOG) have been attracting a surge interest in fabricating soft materials.Although the finding of the gelator molecules has been developed from serendipity to objective design,the achievement of the gelator molecules still needs good design and tedious organic synthesis.In this paper,we proposed a simple and general mixing approach to get the organogel for nearly all the organic compounds and even soluble nanoparticles without any modification.We have designed a universal gelator molecule,which forms organogels with more than 40 kinds of organic solvents from aploar to polar solvents.More interestingly,when other organic compounds or even nanomaterials,which are soluble in certain organic solvents,are mixed with this gelator molecule,they can form organogels no matter whether the individual compounds could form organogel or not.This method is applicable to nearly all kinds of soluble organic compounds and opens an efficient and universal way to fabricate gel materials.展开更多
The development of functional flexible conductive materials can significantly contribute to the improvement of intelligent human–computer integration.However,it is a challenge to endow human–machine interface with p...The development of functional flexible conductive materials can significantly contribute to the improvement of intelligent human–computer integration.However,it is a challenge to endow human–machine interface with perception and response actuation simultaneously.Herein,a customizable and multifunctional electronic conductive organogel is proposed by combining conductive carbon nanotube(CNT)clusters and flexible adhesive organogels.The conductive CNT cluster layers generated on the surface of organogels equip the resulting organogel-based conductors with considerable quasi-superhydrophobicity and increase their potential applicability as highly sensitive stress and strain sensors.In particular,this quasi-superhydrophobicity is insensitive to tensile strain.Based on customizable conductive networks and entropy-driven organogel actuation,the conductive organogels can sense various strain and stress signals and imitate natural organisms with muscle actuation and neurofeedback.This strategy for preparing electronic conductors can enhance the rational design of soft robotics and artificial intelligence devices,facilitating further progress of human-like intelligent systems.展开更多
A series of cholesterol-appended quinacridone (QA) derivatives 1a-1d have been synthesized,in which 1b and 1c could form stable organogels in a wide range of organic solvents upon ultrasound irradiation.Field emission...A series of cholesterol-appended quinacridone (QA) derivatives 1a-1d have been synthesized,in which 1b and 1c could form stable organogels in a wide range of organic solvents upon ultrasound irradiation.Field emission scanning electronic microscope (FESEM) and transmission electron microscopy (TEM) of xerogels or precipitates indicated that 1b and 1c formed 1D fibrous nanostructure,while 1a assembled into 3D flower-like microstructures.The ultrasound-induced organogel process was characterized by kinetic UV-vis and photoluminescence spectroscopic methods suggesting the formation of ?-? aggregates in the gel state.Experimental results demonstrated that the ultrasound could promote molecules to contact frequently in the solution and induce semistable initial aggregates,which propagate to form nano/micro superstructures.The aggregation model was optimized by semiempirical AM1 calculation suggesting the hierarchical self-assembly process.In addition,the formed xerogel film exhibited mechanochromic property,and the phase transition process was accompanied by the fluorescence changes between yellowish green and orange.展开更多
Herein,we present a facile strategy to prepare versatile aluminum oxide subnanometer nanosheets with oleic acid and stearic acid ligands(OA-Al SNSs and SA-Al SNSs,respectively).The size effect endows subnanosheets wit...Herein,we present a facile strategy to prepare versatile aluminum oxide subnanometer nanosheets with oleic acid and stearic acid ligands(OA-Al SNSs and SA-Al SNSs,respectively).The size effect endows subnanosheets with abundant acting sites,remarkable intermolecular interactions,and unique polymer-like properties,including flexibility,viscoelasticity,and sol-gel transitions,which is quite different from traditional inorganic materials.Consequently,subnanosheets could form freestanding organogels and OA-Al SNSs exhibit satisfying semisolidification of various solvents,making it an intriguing candidate for the safe storage and transportation of solvents.Furthermore,SA-Al SNSs exhibit excellent adhesive properties of high strength on diverse substrates,and it is easy to erase it without any damage,demonstrating the promising prospects in practical applications.展开更多
Self-healing hydrogels utilize inherent intermolecular forces to autonomously heal physical damage resulting from excessive strain,pressure,or tearing.Applying these materials in soft robotics and tissue engineering c...Self-healing hydrogels utilize inherent intermolecular forces to autonomously heal physical damage resulting from excessive strain,pressure,or tearing.Applying these materials in soft robotics and tissue engineering could be beneficial.On the other hand,their efficacy in stretchable and mechanically resistant circuits is hindered by their limited electrical conductivity.展开更多
A novel nanomagnetic organogel was synthesized by in situ emulsion polymerization-crosslinking method using dodecyl methacrylate(DDMA) and styrene(St) as monomers, divinylbenzene(DVB) as a crosslinking agent, azobisis...A novel nanomagnetic organogel was synthesized by in situ emulsion polymerization-crosslinking method using dodecyl methacrylate(DDMA) and styrene(St) as monomers, divinylbenzene(DVB) as a crosslinking agent, azobisisobutyronitrile(AIBN) as an initiator, and Fe_3O_4 as a nanomagnetic particle. Modification of the network was carried out by inclusion of the multi-walled carbon nanotubes(MWCNT) into the organogel matrix. The structure of the nanocomposite was characterized using FTIR spectroscopy, SEM,TEM, TGA/DTG, VSM, and BET analysis. The effects of various parameters such as the amount of crosslinker, initiator, Fe_3O_4, and reaction time as well as monomer ratio on the oil absorption of the organogel were studied. The synthesized organogel can absorb about35.5, 22.1, 29.86, 14.58, 17.6, 15.3, and 13.7 g·g^(-1) of CHCl_3, toluene, CH_2Cl_2, hexane, crude oil, gasoline, and diesel oil, under the optimized polymerization conditions, respectively. The nanocomposite organogels can be easily separated by a magnetic field after absorption of organic solvents.展开更多
In this paper, the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ^1H NMR and ESI-MS. The duplex emits strong...In this paper, the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ^1H NMR and ESI-MS. The duplex emits strong pure blue light peaking at 448 and 452 nm under UV photoexcitation in solution and solid state, respectively, and its relative photoluminescence quantum efficiency in solution is determined as 0.778 using quinine sulfate as reference. In concentration of 〉40 mmol/L, the duplex can gelate DMSO, and the organogel formed shows good pure blue photoluminescence too. This novel duplex, for its well-defined structure and efficient photoluminescence property, is a prospective candidate for pure blue electroluminescent emitter.展开更多
Oil spills result in tremendous damage to the environment and ecosystem.In this study,several p-alkoxybenzoyl-based gelators(1,2a,2b,2c,3)synthesized from commercially available materials were designed for recovering ...Oil spills result in tremendous damage to the environment and ecosystem.In this study,several p-alkoxybenzoyl-based gelators(1,2a,2b,2c,3)synthesized from commercially available materials were designed for recovering oil from an oil–water mixture.Gels with remarkable gelation ability in various oils were characterized by nuclear magnetic resonance,Fourier transform infrared spectroscopy and X-ray diffraction to study the driving forces of self-assembly.Notably,these gelators could achieve the goal of recycling oil from the oil–water mixture at room temperature.In addition,gelator 2b could be used to remove toxic dyes from aqueous solutions with high efficiency.Therefore,these compounds were considered promising materials for oil spill recovery and dye removal due to their practicality and high efficiency.展开更多
A new method to fabricate metal/conducting polymer composite nanowires is presented by taking silver/polypyrrole composite nanowires as an example. A silver （D-coordinated organogel as template was prepared firstly, ...A new method to fabricate metal/conducting polymer composite nanowires is presented by taking silver/polypyrrole composite nanowires as an example. A silver （D-coordinated organogel as template was prepared firstly, and redox-polymerization of pyrrole took place on the gel fiber, giving product of silver/polypyrrole nanowires. The silver/polypyrrole nanowires were characterized by multiple techniques. This strategy could be carried out in one-step procedure at room temperature, and it proves the utility of coordinated organogels in template synthesis of polymer nanostructures.展开更多
Four coumarin derivatives（4a-4d） with different alkoxy chains were synthesized. It was found that compound 4d showed a better gelation ability than the other compounds, for example, it could self-assemble into organ...Four coumarin derivatives（4a-4d） with different alkoxy chains were synthesized. It was found that compound 4d showed a better gelation ability than the other compounds, for example, it could self-assemble into organogels in various organic fluids via ultrasound treatment or heating-cooling process, whereas compound 4c could only gel in a few mixed solvents and compounds 4a, 4b could not form organogel. The results from fluorescent and FT-IR spectra indicate that π-π interaction had an effect on the formation of the organogels of compound 4d besides H-bonding and van der Waals interaction, which were the driving forces for the self-assembling of compound 4c in gel state. The gel of compound 4d in toluene could emit strong fluorescence under UV irradiation and the [2＋2] cyclo-addition was suggested by ^1H NMR and fluorescence spectroscopy. This light-sensitive organogel might find application in optical materials.展开更多
In this work, we investigated the effect of hydrophobic interactions between the polymeric backbone and chain-end groups on the self-assembly pathway of stearoyl appended side-chain valine（Val）-based poly（methacryl...In this work, we investigated the effect of hydrophobic interactions between the polymeric backbone and chain-end groups on the self-assembly pathway of stearoyl appended side-chain valine（Val）-based poly（methacrylate/acrylate） homopolymers in different organic hydrocarbons. Gelation studies conducted revealed that while polymers with polyacrylate as backbone induces gelation in several organic hydrocarbons, polymers with polymethacrylate in the main-chain significantly hinders macroscopic gelation. Morphology of the organogels was analysed by field emission scanning electron microscopy（FESEM）, and mechanical strengths of the organogels were determined by rheological measurements. Reversible addition-fragmentation chain transfer（RAFT） polymerization chain transfer agents（CTA）s, [R1―S―C=（S）―S―R2] with different ―R1 and ―R2 groups, have been employed to study the effect of structural variation at the chain-end on macroscopic assembly mechanism. We found that the additional interactions between terminal groups via hydrogenbonding or π-π stacking interactions or both help to build up the self-assembly pathway and thereby produces mechanically stable organogels.展开更多
A phase-selective,bis-urea organogelator with a curved bis-naphthalene core was synthesized and characterized.This gelator is capable of gelating a variety of hydrocarbons and oils.The resulting gels have been charact...A phase-selective,bis-urea organogelator with a curved bis-naphthalene core was synthesized and characterized.This gelator is capable of gelating a variety of hydrocarbons and oils.The resulting gels have been characterized by rheology,SEM,and molecular modelling.The gelator can be applied in the powder form for the recovery of a thin layer of petrol oil spill in water.展开更多
A cholesterol-based organogelator bearing an anthraquinone imide （AQI） group was synthesized and characterized. It self-assembled into chiral gels in acetonitrile at low concentrations, which displayed a combination...A cholesterol-based organogelator bearing an anthraquinone imide （AQI） group was synthesized and characterized. It self-assembled into chiral gels in acetonitrile at low concentrations, which displayed a combination of electrochromic and chiroptical properties. Upon electrochemical reduction at -700 mV, the gel exhibited new absorption bands at around 820 nm corresponding to n＊-z＊ （SOMO---~LUMO） transitions of the radical anion of AQI and strong negative Cotton effects in the same spectral region. With further reduction at -1000 mY, a new CD band with a negative Cotton effect in the range from 500 nm to 800 nm appeared concomitant with the variation of absorption spectrum. Thus, with the use of electrochromic AQI chromophore as a switch-responsive unit and the stable gel of compound N-[3fl-cholest- 5-en-3-yl N-（2-aminoethyl） carbamate] anthraquinone-2,3-dicarboxylic imide as a chiral scaffold, a redox-triggered chiroptical switch operating in visible and near-infrared region was realized.展开更多
Photon upconversion(UC)based on triplet-triplet annihilation(TTA)in quasi-solid or solid state has been attracting much research interest due to its great potential applications.To get effective UC,precisely controlle...Photon upconversion(UC)based on triplet-triplet annihilation(TTA)in quasi-solid or solid state has been attracting much research interest due to its great potential applications.To get effective UC,precisely controlled donor-acceptor interaction is vitally important.Chiral self-assembly provides a powerful approach for sophisticated regulation of molecular interaction.Here we report a chiral self-assembly controlled TTA-UC system composed of chiral acceptor and achiral donor.It is found that racemic mixture of acceptors could form straight fibrous nanostructures,which show strong UC emission,while chiral assemblies for homochiral acceptors emit weak upconverted light.The racemic assemblies allow efficient triplet-triplet energy transfer(TTET)and further realize efficient UC emission,while the homochiral assemblies from chiral acceptor produce twisted nanostructures,suppressing efficient triplet energy transfer and annihilation.The establishment of such chiral self-assembly controlled UC system highlights the potential applications of triplet fusion in optoelectronic materials and provides a new perspective for designing highly effective UC systems.展开更多
L-phenylalanine-derived polymerizable organogel, N’-octadecyl-Nα-(4-vinyl)-benzoyl-L-phenylalanineami- de (4) has been prepared according to the procedure described elsewhere. Compound 4 was successfully polymerized...L-phenylalanine-derived polymerizable organogel, N’-octadecyl-Nα-(4-vinyl)-benzoyl-L-phenylalanineami- de (4) has been prepared according to the procedure described elsewhere. Compound 4 was successfully polymerized by surface initiated atom transfer radical polymerization (ATRP) from the initiator grafted silica particles (sil-poly4). It was also telomerized with 3-mercaptopropyltrimethoxysilane (MPS) and the telomer (T4) was grafted on to silica (sil-T4). TGA and elemental analysis measurement revealed that higher amount of polymer can graft by ATRP process than that of “grafting to” strategy. The results of 13C CP/MAS NMR measurement showed that the N-alkyl chain of the grafted polymers for both sil-poly4 and sil-T4 remained as less ordered gauche conformational form on silica surface and no inversion to trans form was occurred until temperature is increased up to 50?C. The retention of alkylbenzene samples showed that sil-poly4 prepared by “grafting from” method yielded extremely higher retention than conventional C18 phase however, sil-T4 prepared by conventional “grafting to” method showed lower retention than C18 phase. Aspects of molecular recognition were evaluated by the retention studies of a series of polycyclic aromatic hydrocarbons (PAHs) and aromatic positional isomers. We have observed sil-T4 yielded slightly higher selectivity for PAHs than sil-poly4 regardless the fact that it has low surface coverage and lower hydrophobic interactions. The enhanced selectivity observed for sil-T4 than C18 phases and sil-poly4 can be explained by the π - π interactions between the vip PAHs and carbonyl groups present in the polymer chain. In addition the aromatic moieties of compound 4 that aggregates through π - π interactions also contribute to the separation of PAHs for both sil-poly4 and sil-T4. The minimal π - π interactions between the carbonyl groups and vip molecules for sil-poly4 probably due to the presence of long chain initiator which restrict the polymer to form order thin layer over silica surface.展开更多
文摘In the present study,gel formulations of organogels,hydrogels,and oleo-hydrogel(bigels)were evaluated as transdermal drug delivery systems for diltiazem HCL(DH).Organogels were prepared using soya-bean oil(SO)as a solvent and span 60(Sp 60),cetyl alcohol(CA)or lecithinpluronic(PLO)as organogelators without and with different surfactants(2%w/w)namely span 80(Sp80),tween 20(T20)and tween 80(T80).On the other hand,hydrogels were formulated using Hydroxypropyl-methylcellulose(HPMC)polymer and bigels were prepared by mixing organogels with HPMC hydrogels.The prepared gels were analyzed microscopically,thermally by DTA and for pH,and viscosity.The effect of gelator used,surfactant types and pH of the sink on DH release from cellophane membrane was investigated.In addition,the DH permeability across the rabbit skin was evaluated.Finally,the in vivo performance of various gel formulationswas assessed based on the hypotensive effects of the drug using hypertensive albino male rat models.The microscopical analysis indicated that the solid fibers formed by gelator particles form the backbone of the organogels while bigels appeared as emulsion like.The addition of surfactants showed an increase in organogel viscosity.The thermal analysis of organogels indicated that the drug present in amorphous not in crystalline form.The release studies indicated that DH release from organogels,hydrogels and bigels could be controlled.The included surfactants decreased the DH release and permeation from organogels compared to those without surfactants using either Sp60 or CA.HPMC hydrogel and Bigels showed higher DH release and permeation rates when compared to organogels.The percent DH released in different pH values was in the following descending order:pH5.5>pH1.2>pH6.8>pH7.4.The in vivo antihypertensive activity of DH using different transdermal gels is arranged as following:hydrogels>PLO organogel>bigel>Sp 60 organogel.
基金the financial support from the National Natural Science Foundation of China(NSFC)(Nos.51903253,51879292)Natural Science Foundation of Guangdong Province of China(No.2019A1515011150)。
文摘Owing to their inherent semi-solid property and lubricant ability,organogels manifest various unique characteristics and serve as promising candidates for antifouling.However,the poor mechanical properties of organogels often limit their practical applications.Herein,we report a simple and effective method to prepare organogels with reinforced mechanical performance and surface lubricant ability with the synergistic roles played by oleophobic and oleophilic chains.The rigid oleophobic chains have a poor affinity to lubricating solvent,which gives rise to high oleophobic interactions between polymer networks;the soft oleophilic chains possess a high affinity to the low surface energy solvent,which lead to high solvent content to maintain the satisfactory lubricant capacity.The organogel of oleophobic methyl methacrylate(MMA)and oleophilic lauryl methacrylate(LMA)is chosen as a representative example to illustrate this concept.With the optimal composition,the as-prepared organogels offer satisfactory tensile fracture stress,fracture strain,Young’s modulus,toughness,and tearing fracture energy of 480 k Pa,550%,202 k Pa,1.14 MJ m,and 5.14 k J m,respectively,which are far beyond the classical PLMA organogels.Furthermore,the biofouling resistance tests demonstrate 4 to 9-fold reduction of protein and bacteria adhesion on the reinforced organogels surface in comparison to the glass substrate and solvent-free dry organogels.This simple and effective approach to toughen organogels,we hope,can be applied in various fields with different practical functional requirements in the future.
基金supported by the Science and Technology Innovation Commission of Shenzhen,China(Nos.KQJSCX20180328095517269 and JCYJ20170818143131729)。
文摘Fluorescent supramolecular nucleoside-based organogels or hydrogels have attracted increasing attention owing to their tunable stability,drug delivery,tissue engineering,and inherent biocompatibility for applications in designing sensors.As the temperature of a constant TPE-Octa-dU gelato r at MGC as low as 0.2 wt%was increased with gel to sol transition,a progressive decrease in the fluorescence intensity was observed.~1 H NMR study in ethanol-d_(6)/H_(2)O revealed the existence of intermolecular hydrogen-bond interaction between uridine nucleobase and triazole moieties.Based on these experiments,thus organogels induced by hydrogen bonding can promote an aggregation-induced emission(AIE)of TPE moiety.Thermoreversible gelation properties have been investigated systematically,including AIE-shapemorphing architecture owing to their unique solid-liquid interface and easy processability.At the same line,the related TPE-EdU derivative which was synthesized from 5-ethynyl-2'-deoxyuridine does not delive r organogels or hydrogels,a nd under similar circumstances TPE moiety of TPE-EdU does not efficiently exhibit AIE phenomenon either.
基金supported by the National Natural Science Foundation of China(22422108,22171194,22471182,22271201)the Fundamental Research Funds for the Central Universities(20826041D4117).
文摘Supramolecular organogels were highly promising matrices for triplet-triplet annihilation-based upconversion(TTA-UC),but the dispersion and diffusion of the UC components were greatly relied on the microscopically interconnected solution phase in gels.Herein,12-hydroxystearic acid(CA)and its derivatives with different alkyl chain(CA3,CA4,CA6 and CA8)were synthesized as low-molecular-weight gelators(LMMGs),and D-1 with CA attached on DPA unit was synthesized as annihilator.It was found that by co-assembling D-1 with the LMMGs,the DPA units were uniformly dispersed in the gel network regardless of whether there was a solvent or not.By chemically tuning LMMGs to optimize the morphologies of organogels,the DPA units were orderly arranged in the gel network,and showing efficient UC emission in CA,CA3,and CA8 which showed more regular morphologies.UC quantum yield of up to 13.4%(out of 50%maximum)was achieved in CA3 organogel.Moreover,when all solvents were removed from the organogels,D-1 also showed significant UC emissions,which was more than 6-fold higher than that of DPA,indicating that co-assembling the annihilator with the matrix to achieve an order arrangement presented an efficient strategy towards efficient TTA-UC in solid state.
基金supported by the Basic Science Research Program(2023R1A2C3004336,RS-202300243807)&Regional Leading Research Center(RS-202400405278)through the National Research Foundation of Korea(NRF)grant funded by the Korea Government(MSIT)。
文摘Wearable sensors integrated with deep learning techniques have the potential to revolutionize seamless human-machine interfaces for real-time health monitoring,clinical diagnosis,and robotic applications.Nevertheless,it remains a critical challenge to simultaneously achieve desirable mechanical and electrical performance along with biocompatibility,adhesion,self-healing,and environmental robustness with excellent sensing metrics.Herein,we report a multifunctional,anti-freezing,selfadhesive,and self-healable organogel pressure sensor composed of cobalt nanoparticle encapsulated nitrogen-doped carbon nanotubes(CoN CNT)embedded in a polyvinyl alcohol-gelatin(PVA/GLE)matrix.Fabricated using a binary solvent system of water and ethylene glycol(EG),the CoN CNT/PVA/GLE organogel exhibits excellent flexibility,biocompatibility,and temperature tolerance with remarkable environmental stability.Electrochemical impedance spectroscopy confirms near-stable performance across a broad humidity range(40%-95%RH).Freeze-tolerant conductivity under sub-zero conditions(-20℃)is attributed to the synergistic role of CoN CNT and EG,preserving mobility and network integrity.The Co N CNT/PVA/GLE organogel sensor exhibits high sensitivity of 5.75 k Pa^(-1)in the detection range from 0 to 20 k Pa,ideal for subtle biomechanical motion detection.A smart human-machine interface for English letter recognition using deep learning achieved 98%accuracy.The organogel sensor utility was extended to detect human gestures like finger bending,wrist motion,and throat vibration during speech.
基金supported by the National Natural Science Foundation of China (50673095 and 21021003)the Basic Research Development Program (2007CB808005 and 2009CB930802)the Fund of the Chinese Academy of Sciences
文摘Low-molecular-weight organogels(LMOG) have been attracting a surge interest in fabricating soft materials.Although the finding of the gelator molecules has been developed from serendipity to objective design,the achievement of the gelator molecules still needs good design and tedious organic synthesis.In this paper,we proposed a simple and general mixing approach to get the organogel for nearly all the organic compounds and even soluble nanoparticles without any modification.We have designed a universal gelator molecule,which forms organogels with more than 40 kinds of organic solvents from aploar to polar solvents.More interestingly,when other organic compounds or even nanomaterials,which are soluble in certain organic solvents,are mixed with this gelator molecule,they can form organogels no matter whether the individual compounds could form organogel or not.This method is applicable to nearly all kinds of soluble organic compounds and opens an efficient and universal way to fabricate gel materials.
基金State Key Program of National Natural Science Foundation of China,Grant/Award Number:52130303National Natural Science Foundation of China,Grant/Award Numbers:51803151,51973152,51973151。
文摘The development of functional flexible conductive materials can significantly contribute to the improvement of intelligent human–computer integration.However,it is a challenge to endow human–machine interface with perception and response actuation simultaneously.Herein,a customizable and multifunctional electronic conductive organogel is proposed by combining conductive carbon nanotube(CNT)clusters and flexible adhesive organogels.The conductive CNT cluster layers generated on the surface of organogels equip the resulting organogel-based conductors with considerable quasi-superhydrophobicity and increase their potential applicability as highly sensitive stress and strain sensors.In particular,this quasi-superhydrophobicity is insensitive to tensile strain.Based on customizable conductive networks and entropy-driven organogel actuation,the conductive organogels can sense various strain and stress signals and imitate natural organisms with muscle actuation and neurofeedback.This strategy for preparing electronic conductors can enhance the rational design of soft robotics and artificial intelligence devices,facilitating further progress of human-like intelligent systems.
基金supported by the National Natural Science Foundation of China (50773027 and 50733002)the National Basic Research Development Program (2009CB939700)111 Project (B06009)
文摘A series of cholesterol-appended quinacridone (QA) derivatives 1a-1d have been synthesized,in which 1b and 1c could form stable organogels in a wide range of organic solvents upon ultrasound irradiation.Field emission scanning electronic microscope (FESEM) and transmission electron microscopy (TEM) of xerogels or precipitates indicated that 1b and 1c formed 1D fibrous nanostructure,while 1a assembled into 3D flower-like microstructures.The ultrasound-induced organogel process was characterized by kinetic UV-vis and photoluminescence spectroscopic methods suggesting the formation of ?-? aggregates in the gel state.Experimental results demonstrated that the ultrasound could promote molecules to contact frequently in the solution and induce semistable initial aggregates,which propagate to form nano/micro superstructures.The aggregation model was optimized by semiempirical AM1 calculation suggesting the hierarchical self-assembly process.In addition,the formed xerogel film exhibited mechanochromic property,and the phase transition process was accompanied by the fluorescence changes between yellowish green and orange.
基金supported by NSFC(22241502,22035004,and 22250710677).
文摘Herein,we present a facile strategy to prepare versatile aluminum oxide subnanometer nanosheets with oleic acid and stearic acid ligands(OA-Al SNSs and SA-Al SNSs,respectively).The size effect endows subnanosheets with abundant acting sites,remarkable intermolecular interactions,and unique polymer-like properties,including flexibility,viscoelasticity,and sol-gel transitions,which is quite different from traditional inorganic materials.Consequently,subnanosheets could form freestanding organogels and OA-Al SNSs exhibit satisfying semisolidification of various solvents,making it an intriguing candidate for the safe storage and transportation of solvents.Furthermore,SA-Al SNSs exhibit excellent adhesive properties of high strength on diverse substrates,and it is easy to erase it without any damage,demonstrating the promising prospects in practical applications.
文摘Self-healing hydrogels utilize inherent intermolecular forces to autonomously heal physical damage resulting from excessive strain,pressure,or tearing.Applying these materials in soft robotics and tissue engineering could be beneficial.On the other hand,their efficacy in stretchable and mechanically resistant circuits is hindered by their limited electrical conductivity.
文摘A novel nanomagnetic organogel was synthesized by in situ emulsion polymerization-crosslinking method using dodecyl methacrylate(DDMA) and styrene(St) as monomers, divinylbenzene(DVB) as a crosslinking agent, azobisisobutyronitrile(AIBN) as an initiator, and Fe_3O_4 as a nanomagnetic particle. Modification of the network was carried out by inclusion of the multi-walled carbon nanotubes(MWCNT) into the organogel matrix. The structure of the nanocomposite was characterized using FTIR spectroscopy, SEM,TEM, TGA/DTG, VSM, and BET analysis. The effects of various parameters such as the amount of crosslinker, initiator, Fe_3O_4, and reaction time as well as monomer ratio on the oil absorption of the organogel were studied. The synthesized organogel can absorb about35.5, 22.1, 29.86, 14.58, 17.6, 15.3, and 13.7 g·g^(-1) of CHCl_3, toluene, CH_2Cl_2, hexane, crude oil, gasoline, and diesel oil, under the optimized polymerization conditions, respectively. The nanocomposite organogels can be easily separated by a magnetic field after absorption of organic solvents.
基金supported by the Foundation of Science and Technology Bureau,Sichuan Province(No. 2006j13-141)the National Natural Science Foundation of China(No.20672076).
文摘In this paper, the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ^1H NMR and ESI-MS. The duplex emits strong pure blue light peaking at 448 and 452 nm under UV photoexcitation in solution and solid state, respectively, and its relative photoluminescence quantum efficiency in solution is determined as 0.778 using quinine sulfate as reference. In concentration of 〉40 mmol/L, the duplex can gelate DMSO, and the organogel formed shows good pure blue photoluminescence too. This novel duplex, for its well-defined structure and efficient photoluminescence property, is a prospective candidate for pure blue electroluminescent emitter.
文摘Oil spills result in tremendous damage to the environment and ecosystem.In this study,several p-alkoxybenzoyl-based gelators(1,2a,2b,2c,3)synthesized from commercially available materials were designed for recovering oil from an oil–water mixture.Gels with remarkable gelation ability in various oils were characterized by nuclear magnetic resonance,Fourier transform infrared spectroscopy and X-ray diffraction to study the driving forces of self-assembly.Notably,these gelators could achieve the goal of recycling oil from the oil–water mixture at room temperature.In addition,gelator 2b could be used to remove toxic dyes from aqueous solutions with high efficiency.Therefore,these compounds were considered promising materials for oil spill recovery and dye removal due to their practicality and high efficiency.
基金The financial support from the National Natural Science Foundation of China(Nos.20574041 and 20874055)Hi-tech Research and Development Program(863 plan)of China(No.SQ2009AA06XK1482459)
文摘A new method to fabricate metal/conducting polymer composite nanowires is presented by taking silver/polypyrrole composite nanowires as an example. A silver （D-coordinated organogel as template was prepared firstly, and redox-polymerization of pyrrole took place on the gel fiber, giving product of silver/polypyrrole nanowires. The silver/polypyrrole nanowires were characterized by multiple techniques. This strategy could be carried out in one-step procedure at room temperature, and it proves the utility of coordinated organogels in template synthesis of polymer nanostructures.
基金Sypported by National Natural Science Foundation of China(No.20574027)Program for New Century Excellent Talents in University.
文摘Four coumarin derivatives（4a-4d） with different alkoxy chains were synthesized. It was found that compound 4d showed a better gelation ability than the other compounds, for example, it could self-assemble into organogels in various organic fluids via ultrasound treatment or heating-cooling process, whereas compound 4c could only gel in a few mixed solvents and compounds 4a, 4b could not form organogel. The results from fluorescent and FT-IR spectra indicate that π-π interaction had an effect on the formation of the organogels of compound 4d besides H-bonding and van der Waals interaction, which were the driving forces for the self-assembling of compound 4c in gel state. The gel of compound 4d in toluene could emit strong fluorescence under UV irradiation and the [2＋2] cyclo-addition was suggested by ^1H NMR and fluorescence spectroscopy. This light-sensitive organogel might find application in optical materials.
基金Council of Scientific and Industrial Research (CSIR), Government of India, New Delhi, India, for financial support (Project: 02(0271)/16/EMR-II dated 02.12.2016)
文摘In this work, we investigated the effect of hydrophobic interactions between the polymeric backbone and chain-end groups on the self-assembly pathway of stearoyl appended side-chain valine（Val）-based poly（methacrylate/acrylate） homopolymers in different organic hydrocarbons. Gelation studies conducted revealed that while polymers with polyacrylate as backbone induces gelation in several organic hydrocarbons, polymers with polymethacrylate in the main-chain significantly hinders macroscopic gelation. Morphology of the organogels was analysed by field emission scanning electron microscopy（FESEM）, and mechanical strengths of the organogels were determined by rheological measurements. Reversible addition-fragmentation chain transfer（RAFT） polymerization chain transfer agents（CTA）s, [R1―S―C=（S）―S―R2] with different ―R1 and ―R2 groups, have been employed to study the effect of structural variation at the chain-end on macroscopic assembly mechanism. We found that the additional interactions between terminal groups via hydrogenbonding or π-π stacking interactions or both help to build up the self-assembly pathway and thereby produces mechanically stable organogels.
基金financially supported by the National Natural Science Foundation of China(Nos.21302090,21572097)South University of Science and Technology of Chinathe Shenzhen special funds for the development of biomedicine,internet,new energy,and new material industries(No. JCYJ20150331101823694)
文摘A phase-selective,bis-urea organogelator with a curved bis-naphthalene core was synthesized and characterized.This gelator is capable of gelating a variety of hydrocarbons and oils.The resulting gels have been characterized by rheology,SEM,and molecular modelling.The gelator can be applied in the powder form for the recovery of a thin layer of petrol oil spill in water.
基金financially supported by the National Natural Science Foundation of China(Nos.20674001,20325415, 20834001)the Research Fund for Doctoral Program of Higher Education of MOE of China(No.20060001029)
文摘A cholesterol-based organogelator bearing an anthraquinone imide （AQI） group was synthesized and characterized. It self-assembled into chiral gels in acetonitrile at low concentrations, which displayed a combination of electrochromic and chiroptical properties. Upon electrochemical reduction at -700 mV, the gel exhibited new absorption bands at around 820 nm corresponding to n＊-z＊ （SOMO---~LUMO） transitions of the radical anion of AQI and strong negative Cotton effects in the same spectral region. With further reduction at -1000 mY, a new CD band with a negative Cotton effect in the range from 500 nm to 800 nm appeared concomitant with the variation of absorption spectrum. Thus, with the use of electrochromic AQI chromophore as a switch-responsive unit and the stable gel of compound N-[3fl-cholest- 5-en-3-yl N-（2-aminoethyl） carbamate] anthraquinone-2,3-dicarboxylic imide as a chiral scaffold, a redox-triggered chiroptical switch operating in visible and near-infrared region was realized.
基金supported by the National Natural Science Foundation of China(Nos.21802027,51673050,91856115)the Youth Foundation of Department of Science and Technology of Jilin Province of China(No.20160520136JH)the Scientific Research Project of Education Department of Jilin Province of China(No.2016319)
文摘Photon upconversion(UC)based on triplet-triplet annihilation(TTA)in quasi-solid or solid state has been attracting much research interest due to its great potential applications.To get effective UC,precisely controlled donor-acceptor interaction is vitally important.Chiral self-assembly provides a powerful approach for sophisticated regulation of molecular interaction.Here we report a chiral self-assembly controlled TTA-UC system composed of chiral acceptor and achiral donor.It is found that racemic mixture of acceptors could form straight fibrous nanostructures,which show strong UC emission,while chiral assemblies for homochiral acceptors emit weak upconverted light.The racemic assemblies allow efficient triplet-triplet energy transfer(TTET)and further realize efficient UC emission,while the homochiral assemblies from chiral acceptor produce twisted nanostructures,suppressing efficient triplet energy transfer and annihilation.The establishment of such chiral self-assembly controlled UC system highlights the potential applications of triplet fusion in optoelectronic materials and provides a new perspective for designing highly effective UC systems.
文摘L-phenylalanine-derived polymerizable organogel, N’-octadecyl-Nα-(4-vinyl)-benzoyl-L-phenylalanineami- de (4) has been prepared according to the procedure described elsewhere. Compound 4 was successfully polymerized by surface initiated atom transfer radical polymerization (ATRP) from the initiator grafted silica particles (sil-poly4). It was also telomerized with 3-mercaptopropyltrimethoxysilane (MPS) and the telomer (T4) was grafted on to silica (sil-T4). TGA and elemental analysis measurement revealed that higher amount of polymer can graft by ATRP process than that of “grafting to” strategy. The results of 13C CP/MAS NMR measurement showed that the N-alkyl chain of the grafted polymers for both sil-poly4 and sil-T4 remained as less ordered gauche conformational form on silica surface and no inversion to trans form was occurred until temperature is increased up to 50?C. The retention of alkylbenzene samples showed that sil-poly4 prepared by “grafting from” method yielded extremely higher retention than conventional C18 phase however, sil-T4 prepared by conventional “grafting to” method showed lower retention than C18 phase. Aspects of molecular recognition were evaluated by the retention studies of a series of polycyclic aromatic hydrocarbons (PAHs) and aromatic positional isomers. We have observed sil-T4 yielded slightly higher selectivity for PAHs than sil-poly4 regardless the fact that it has low surface coverage and lower hydrophobic interactions. The enhanced selectivity observed for sil-T4 than C18 phases and sil-poly4 can be explained by the π - π interactions between the vip PAHs and carbonyl groups present in the polymer chain. In addition the aromatic moieties of compound 4 that aggregates through π - π interactions also contribute to the separation of PAHs for both sil-poly4 and sil-T4. The minimal π - π interactions between the carbonyl groups and vip molecules for sil-poly4 probably due to the presence of long chain initiator which restrict the polymer to form order thin layer over silica surface.
